贪吃蛇游戏帮助 - 不使用Pygame(Python)

Question

目前正在使用python，import.draw，没有pygame设计一个贪吃蛇游戏！我的大部分游戏都完成了，而且效果很好，除了任何时候点击箭头(向上、向下、向左或向右(时，蛇的长度就会变大，这不是我想要的，因为只有当蛇吃了苹果时，长度才会变大！这是我的代码： 导入抽奖 导入随机

Draw.setCanvasSize(600,600)
masterList = [[None for col in range(30)] for row in range(30)]
def startscreen():  #WELCOME SCREEN
#set screen
#(may change to loop later)
Draw.setBackground(Draw.CYAN)
Draw.setColor(Draw.RED)
Draw.filledRect(0,100,600,200)
Draw.setColor(Draw.GREEN)
Draw.filledRect(0,200,600,200)
Draw.setColor(Draw.PINK)
Draw.filledRect(0,200,600,200)
Draw.setColor(Draw.BLUE)
Draw.filledRect(0,300,600,200)
Draw.setColor(Draw.YELLOW)
Draw.filledRect(0,400,600,200)
Draw.setColor(Draw.VIOLET)
Draw.filledRect(0,500,600,200)
Draw.setFontSize(80)
Draw.setFontFamily("Courier")
a = "SNAKE GAME"
Draw.setColor(Draw.BLACK)
Draw.string(a,50,220)
Draw.setFontSize(35)
Draw.string("CLICK ANYWHERE TO CONTINUE",30,330)
def clickAnywhere():
while True:
    if Draw.mousePressed():
        return True
#code for press enter to continue using draw package and keys
def playGame(size):
#choose starting point for apple
appleX = random.randrange(0, 580, 20)
appleY = random.randrange(0, 580, 20)  
positionApple = random.randrange(0, 580, 20) 
masterList[positionApple//20][positionApple//20] = 'a'
# initial position of snake in middle
lengthSnake = 4 # four boxes
positionSnakeX = 300
positionSnakeY = 300
for i in range(15, 19):
    masterList[15][i] = 'x'
drawTheBoard(appleX,appleY, positionSnakeX, positionSnakeY,lengthSnake)
#while positionSnake != 0 and positionSnake != 600:
while True:
    # check if user pressed a key to change snake direction
    if Draw.hasNextKeyTyped():
        newKey = Draw.nextKeyTyped()
        if newKey == "Left":
            positionSnakeX -= 20
            lengthSnake += 1
        elif newKey == "Right":
            positionSnakeX += 20   
            lengthSnake += 1
        elif newKey == "Up":
            positionSnakeY -= 20 
            lengthSnake += 1
        elif newKey == "Down":
            positionSnakeY += 20  
            lengthSnake += 1
        drawTheBoard(appleX,appleY, positionSnakeX, positionSnakeY, 
lengthSnake)

    # if snake hit the apple, then add a box to the snake
    if hitApple(positionSnakeX, positionSnakeY, positionApple, positionApple):
        lengthSnake += 1
        masterList[positionApple/20][positionApple/20] = None
        positionApple = random.randrange(0, 580, 20)
        masterList[positionApple/20][positionApple/20] = 'a'
    #check if snake hit wall using hitWall()
  #      if hitWall(positionSnake, positionSnake):
   #          return False # will this break the while loop 
    # check if snake hit itself
    # otherwise draw the board
    #    drawTheBoard(positionApple, positionSnakeX, positionSnakeY, 
   lengthSnake) # function that clears and resets board after each round
    #def moveSnake(s,dx,dy):
   #head= s[0]
   #news= [[head[0] + dy, head[1]+dx]]+s[0:-1]]
   #return news
 def drawTheBoard(appleX,appleY,snakeX,snakeY,lengthSnake):
#clear Canvas
Draw.clear()
#Draw Snake using for loop to draw the number of rectangles corresponding to
#how many boxes in 2D list it has
Draw.picture("snakeBackground.gif",0,0)
Draw.setColor(Draw.BLACK)
for i in range(lengthSnake):
    Draw.filledRect(snakeX+(20*i), snakeY, 20, 20)
    # change the x, y coordinates based on 2D list
# Draw Apple
Draw.setColor(Draw.RED)
drawApple(appleX, appleY)
if snakeX == appleX and snakeY == appleY:
    drawApple()
    #return true
    #if snake hit wall
    #return False
Draw.show()
 def drawApple(appleX, appleY):
   #appleX = random.randrange(0, 580, 20) 
   #appleY = random.randrange(0, 580, 20) 
   Draw.setColor(Draw.RED)
   Draw.filledOval(appleX, appleY, 20, 20)       
 def hitApple(snakeX, snakeY, appleX, appleY):
if (appleX < snakeX < appleX + 20) or (appleY < snakeY < appleY + 20):
    return True
return False
 #def hitWall(snakeCoords):
#use x, y coordinates to check if snake hit wall, returning True or False
#if snake's x is less than 0 or x is greater than or equal to numCols
#if y is less than 0 or y is greater than or equal to numRows
#return True
# Else, return False
# (0,600) is considered hitting the wall
 def main():
startscreen()
if clickAnywhere():
    Draw.clear()
#clear the screen
snakeSize = 4
#for each of x times
#ans= playGame(size)
#If ans= playGame(size):
#snakeSize += 1
playGame(snakeSize)

# Draw.show(( 主((

Answer 1

你执行

lengthSnake += 1

每次Draw.hasNextKeyTyped()都是真实的(键是"左"/"右"/"上"/"下"(。

Answer 2

有了这个while循环，你告诉计算机每次按下一个键时，都会在蛇的长度上添加一个。

while True:
    # check if user pressed a key to change snake direction
    if Draw.hasNextKeyTyped():
        newKey = Draw.nextKeyTyped()
        if newKey == "Left":
            positionSnakeX -= 20
            lengthSnake += 1
        elif newKey == "Right":
            positionSnakeX += 20   
            lengthSnake += 1
        elif newKey == "Up":
            positionSnakeY -= 20 
            lengthSnake += 1
        elif newKey == "Down":
            positionSnakeY += 20  
            lengthSnake += 1`enter code here`

从每个 if 块中删除长度蛇 += 1。